Carpenter&#39;s gage for drafting rafters and braces.



No. 773,763. PATENTED NOV. 1, 1904. J. F. MQOORMIGK.

CARPENTERS GAGE FOR DRAFTING RAPTERS AND BRACES. 7 APPLICATION FILEDMAR. 9, 1904.

no MODEL. 2 SHEETS-SHEET 1.

lvitnzoow W No. 773,763. PATENTED NOV. 1, 1904.

' J. F. MUGORMIGK. GARPENTERS GAGE FOR DRAPTING RAPTERS AND BRACES.

APPLICATION FILED MAE. 9, 1904.

N0 MODEL. 2SHEBTS-SHBET 2.

I attouwqe,

' I E Z UNITED STATES Patented November 1, 1904.

PATENT OFFICE.

CARPENTERS GAGE FOR DRAFTING RAFTEIRS AND BRACES.

SPECIFICATION forming part of Letters Patent No. 773,763, dated November1, 1904.

Application filed March 9, 1904. Serial No. 197,310. (No model.)

' To all whmn it may concern:

Be it known that 1, JOHN F. MCCORMI K, a citizen of the United States,residing at Churnbusco, in the county of WVhitley and State of Indiana,have invented certain new and useful Improvements in Carpenters Gagesfor Drafting Rafters and Braces, of which the following is aspecification.

This invention provides a square for artificers to enable work to beaccurately and quickly laid off, being especially adapted for carpentersand builders to facilitate the ascertainment of the length of rafters,braces, slant purlin-posts and braces, and the angles at the ends ofsaid parts and the location of mortises in beams, purlin-posts, and thelike to receive the tenoned ends of the braces, struts, and other partsin special work.

For a full description of the invention and the merits thereof and alsoto acquire a knowledge of the details of construction of the means foreffecting the result reference is to be had to the following descriptionand drawings hereto attached.

WVhile the essential and characteristic features of the invention aresusceptible of mod i fication, still the preferred embodiment of theinvention is illustrated in the accompanying drawings, in which Figure 1is a perspective view of the square, showing the application ofdetermining the length of a rafter and the angle at the upper or headend. Fig. 2 is a side view of the square as it appears when adjusted fordetermining the length of a rafter, brace, or like part and the angle atthe head and heel ends thereof. Fig. 3 is a transverse section on theline 3 3 of Fig. 2 looking in the direction of the arrow, parts beingbroken away. Fig. 4 is a side elevation showing the arrangement of theparts when laying off special Work, such as determining the length andangles of a slant purlin-brace. Fig. 5 is a perspective view of thebevel-square. Fig 6 is a section on the line 6 6 of Fig. 4:.

Corresponding and like parts are referred to in the followingdescription and indicated in all the views of the drawings by the samereference characters.

The instrument comprises two parts, a

square and a bevel-square. The square comprises the base member 1, arm2, and straightedge 3. The arm 2 and base member 1 are disposed at aright angle to each other, whereas the straight-edge 3 is adjustablewith reference thereto and in conjunction therewith serves to indicatethe length of braces or diagonals and the angles at opposite endsthereof. The several parts of the square proper and the bevel-square aregraduated as may be desired according to the special work for which theinstrument may be designed. For general application the graduations arelaid off in inches and fractional parts thereof, the inchescorresponding to feet and the subdivisions of the inches to the units ofa foot.

To meet this requirement, the inches are subdivided into twelfths, eachtwelfth representing an inch or unit of a foot when laying off work. Theseveral parts are similarly graduated, so as to secure a correspondenceof indication when laying off work, thereby obviating confusion ornecessitating allowances. The base member 1 generally corresponds to thebeam or horizontal work and the arm 2 to the rise or altitude of thework. The straight-edge 3 represents the brace or diagonal and theindicated distance designated thereon at its points of touching 0rcrossing the parts 1 and 2 corresponds in feet and inches to the lengthof the brace, rafter, or other part, and the angle between the upper endof the straight-edge and the arm 2 will give the cut or angle at thehead end of the work and the angle between the straight-edge and themember 1 will give the angle at the heel or lower end of the work, saidangle being readily determined by the bevel-square, as indicated mostclearly in Fig. 1. The base member 1 is provided withlongitudinal slots4 and 5, which have a right-angular arrangement and intersect, thelongitudinal slot 4 being in the plane of the arm 2 and the longitudinalslot 5 being ina plane at a right angle to the plane of the arm 2. Thestraight-edge 3 is adapted to move freely in the longitudinal slot Landis held in the required adjusted position by means of the clamp-bolt 6,which passes through the slot 5 and a corresponding longitudinal slot 7in the straight-edge.

The slot 5 is closed at its ends, thereby preventing displacement of theclamp-bolt, and for a like reason the slot 7 is closed at its ends. Theslot 4 is open at its outer end to admit of moving the straight-edgefrom one side to the other of the base member 1, according to the natureof the work to be laid out. One end of the straight-edge is inclined orout off at an angle, as shown at 8, thereby admitting of the pointcoming close against the graduated side of the arm 2, which is essentialto accuracy. The opposite end of the straight-edge is square and ispreferably provided with a projection 9, which is at a true right angleto the straight-edge and provides suliicient surface to enable the bladeof the bevel-square to be properly placed when it is desired to use thesquare end of the straightedge, as indicated in Fig. at.

The bevel-square comprises the stock 10 and the blade 11, the latterbeing pivoted to the stool; and adapted to be secured in an adjustedposition by the clamp-bolt 12. The outer side of the stock 10 ischanneled or grooved to provide a longitudinal seat 13 of a width tosnugly receive the arm 2 when the bevelsquare is fitted thereto. An endportion of one wall of the seat 13 is cut away, as indicated at 14, toreceive the blade 11 and admit of the latter lying adjacent to andwholly at one side of the seat 13. A kerf 15 extends into the stock fromone end and separates the same, so as to provide, in effect, movablemembers, which are adapted to be drawn together by means of a elamp-bolt16, so as to secure the bevel-square to the arm 2 in the requiredposition, as indicated in Figs. 1, at, and 6. This construction enablesthe bevelsquare'to be positively secured to the arm 2 at the requiredpoint, thereby enabling the straight-edge to be manipulated and adjustedwithout fear of displacement of the bevel square.

W hen the rise and width of work is given and it is required toascertain the length of the diagonal and the angles between saiddiagonal and the vertical and. the horizontal, the straight-edge 3 ismoved so that its upper end points to a ligure on the arm 2corresponding to the rise and its lower end adjusted so as to cross thebase member 1 at a point corresponding to the width, after which thestraightedge is made secure by tightening the clampbolt 6. The numberindicated on the straightedge at its point of crossing the base member 1corresponds to the length of. the diagonal, and the angles between saidstraight-edge and the parts 1 and 2 correspond to the angles at the endsof the diagonal in order to assure a close fit with the beam and post,as will be readily comprehended. These angles are readily ascertained,by means of the bevel-square, in the manner well understood.

In order to increase the utility of the instrument, the base member 1isprovided at a convenient pointwith a spirit-level17, whereby work maybe leveled and plumbed.

Having thus described the invention, what is claimed as new is 1. Incombination, a square comprising a base member and an arm, astraight-edge adjustable with reference to the arm and base member,means for securing the straight-edge in the adjusted position and abevel-square comprising a stock and pivoted blade, said stock having alongitudinal split or kerf and a seat to receive the aforesaid arm, andmeans for drawing the separated parts of the stock together to clamp thestock upon the arm at the required position, substantially as set forth.

2. In combination with a square comprising a base member and aright-angularly-disposed arm, an adjustable straight-edge, means forsecuring the straight-edge in an adjusted position and a bevel-squarecomprising a stock and a pivoted blade, said stock having a longitudinalseat in one face to receive the aforementioned arm and having a kerf orsplit,

and means for drawing the separated parts of the stock together to clampthe same upon the arm, substantially as set forth.

In testimony whereof I affix my signature in presence of two witnesses.

JOHN F. MCCORMICK. [1,. s] Witnesses:

EDWARD E. FLANAGAN, ALEXANDER B. CRAIG.

